Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/50—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by form
  • D21H21/52—Additives of definite length or shape
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B33/00—Silicon; Compounds thereof
  • C01B33/113—Silicon oxides; Hydrates thereof
  • C01B33/12—Silica; Hydrates thereof, e.g. lepidoic silicic acid
  • C01B33/14—Colloidal silica, e.g. dispersions, gels, sols
  • C01B33/146—After-treatment of sols
  • C01B33/149—Coating
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
  • D21H17/69—Water-insoluble compounds, e.g. fillers, pigments modified, e.g. by association with other compositions prior to incorporation in the pulp or paper
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
  • D21H21/06—Paper forming aids
  • D21H21/10—Retention agents or drainage improvers
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/66—Salts, e.g. alums
• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
  • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
  • D21H17/63—Inorganic compounds
  • D21H17/67—Water-insoluble compounds, e.g. fillers, pigments
  • D21H17/68—Water-insoluble compounds, e.g. fillers, pigments siliceous, e.g. clays

Definitions

• the present invention is concerning cationic nano-particle sols and their use for papermaking. It is a method to use cationic nano-particle sols to remove the contaminants (dissolved and colloidal substances) in aqueous and retain them with paper product.
• the cationic poly-electrolytes can be cationic low molecular weight, high-charged density organic polymers such as cationic polyamine, polyethyleneimine (PEI), cationic ploy-DADMAC,PAM, Polyethylene oxide (PEO) etc.
• PEI polyethyleneimine
• PAM polyethylene oxide
• different aluminum compounds are often present in pulp furnish, including AlCl 3 , Al(NO 3 ) 3 , poly-aluminum compounds and the mixture of them.
• Poly-aluminum complexes may contain chloride, sulfate, phosphate and various anions.People also explore inorganic fillers to function as anionic trash catchers such as talc, kaolin, precipitated calcium carbonate etc. However, white water can not be effectively purified through the above treatments.
• cationic nano-particles to purify white water--better be cationic nano-silica particles to remove dissolved and colloidal substances from pulp suspension and retain them with paper product.
• the main mechanism is thought that cationic nano-particles remove DCS through electro-neutralization, particle bridging flocculation, electrostatic attraction or the synthesized role of them.
• a cationic nano-particle sol is offered, preferably cationic silica sols, the surface area of the stated particles is big than 500 m 2 /g to 5000 m 2 /g, preferably 600 m 2 /g to 5000 m 2 /g, more preferably 800 m 2 /gto 5000 m 2 /g, most preferably 1000 m 2 /g to 5000 m 2 /g.
• the aluminum to surface SiO 2 mol ratio is 1:8 to 30:1, preferably 1:1 to 30:1,more preferably 5:1 to 30:1,most preferably 10:1 to 30:1.
• another cationic nano-particle sol is offered, preferably cationic silica sols, the surface area of the stated particles is big than 200 m 2 /g to 5000 m 2 /g, preferably 500 m 2 /g to 5000 m 2 /g,more preferably 800 m 2 /g to 5000 m 2 /g, most preferably 1000 m 2 /g to 5000 m 2 /g.
• the aluminum to surface SiO 2 mol ratio is 1:1 to 30:1, preferably 3:1 to 30:1,more preferably 5:1 to 30: 1, most preferably 10:1 1 to 30:1.
• the cationic charge of particles is produced by cationic species coated on the surface such as metal species.
• the preparation method is disclosed such as in the US Pat. Nos. 3,007,878 , 3,719,607 .
• the methods for preparing cationic silica sols usually involve that the nano-particle sols are reacted with a basic salt of a polyvalent (a valency of 3-4) metal to give the sol particle a cationic surface charge.
• stabilizers are boric acid, phosphate, alkali metal bases, alkaline earth metal bases, ammonia etc.
• the trivalent metals in the salt are aluminum, chromium, gallium, indium, or thallium.
• tetravalent metals are titanium, germanium, zirconium, stannic tin, cerium, hafnium, and thorium.
• the anions of stronger acids in the metal salts such as Cl -1 , NO 3 -1 , Br -1 and CH 3 CH 2 OO -1 etc are preferably chosen.
• Aluminum salt is preferably due to its low price.
• the cationic nano-particle sol is acidic, pH is low than 7.
• the nano-particle sols are suitably diluted to a concentration of from 0.1 to 2 % by weight before addition to the pulp suspension. Preferably from 0.5 to 1.5 % by weight, more preferably from 0.5 to 1 % by weight.
• the dilution agent is water.
• the amounts of cationic nano-silica particles are from 0.1 kg/ton to 20 kg/ton by weight of cationic silica, as dry, based on the weight of dry fibers, preferably from 1 kg/ton to 6 kg/ton, more preferably from 1 kg/ton to 3 kg/ton.
• the preparation of cationic nano-particles sols includes: that silica sols, or acidic deionized silica sols or acidic polymeric silicic acid is reacted with a basic salt of polyvalent metal.
• the ratio of metal atoms in the salt to silica in the aqueous is from 2 ⁇ 10 -5 A :1 to 2 ⁇ 10 -3 A :1,where A is the surface area of particles in the aqueous sol m 2 /g.
• the reaction is conducted under heating until the pH remains constant. Then the mixture is stabilized by adding stabilizer.
• the present invention can be used for various fiber pulp for papermaking stock.
• the fiber pulp can be chemical or mechanical pulp of softwood and hardwood such as sulfate pulp, sulfite pulp, thermomechanical pulp(TMP), Groundwood pulp/Stone Groundwood pulp, Refiner Groundwood pulp (RMP), Chemi-mechanical pulp and the recycle pulp and nonwood pulp can also be used.
• Papermaking stock can contain conventional filler such as kaolin, TiO 2 , Talc, gypsum, precipitated calcium carbonate (PCC)/ ground calcium carbonate (GCC), etc. and the additives such as dry strength agent, wet strength agent, dye etc.
• the cationic nanoparticle sols should be added to pulp suspension before filler, pH of pulp suspension is 4-9, consistency of pulp suspension can be 0.2%-3.5% by weight.
• the removed DCS is retained with paper sheet.
• the present invention can be used in combination with any other organic aids and additives.
• the dissolve and colloidal substances in the aqueous are removed but no negative effects to paper quality.
• 50% COD is reduced, 70%-80% cationic nano-particles is retained with paper sheets.
• the retention of fiber pulp and the operation of paper production is improved.
• Less amount of cationic nano-particles sols can bring a high efficiency and the manipulating is easy.
• the present invention is widely suitable to various paper and paperboard production under various conditions.
• Fiber pulp is 100% spruce TMP. With HCl and NaOH, the pulp suspension is adjusted to 6.5.
• Cationic nano-particle sol A contains 5.9% Al 2 O 3 by weight and 9.9% SiO 2 % by weight.
• Cationic nano-particle sol B contains 25.9 % Al 2 O 3 by weight and 3.9 % SiO 2 % by weight.
• the dosage is calculated based on dry weight of cationic nano-particle sols and fiber pulp. Under 1000 rpm stirring, cationic nano-particle sols are added to dynamic drainage jar with the closed exit. The pulp suspension is agitated for 3 mins. 100 ml of first-pass filtrate is collected and the water sample of DCS is obtained by centrifugation. COD is measured following the standard method SCAN-CM 45:91. The results are shown in table 1
• Cationic nanoparticle sol A is used, fiber pulp is 100% spruce TMP. With HCl and NaOH, the pH of pulp suspension is adjusted to 8.5. Other steps are the same as those in example 1. The results are shown in table 2
• Cationic nanoparticle sol A is used, fiber pulp is 100% spruce TMP, the consistency of pulp suspension is 2- 10 g/I. The pH of pulp suspension is 4-9. The other steps are the same as those in example 1. The COD removal increases 10-26 %.
• Cationic nanoparticle sol A is added to fiber pulp suspension, the consistency of pulp suspension is 1.63 g/I.
• the handsheets are formed in sheetmaking mould of laboratory. The retention of SiO 2 and paper properties are measured following the standard method SCAN-P. Fiber pulp is spruce TMP, Kraft pine pulp, and the mixture of the spruce TMP and kraft pine pulp respectively.
• the dosage of cationic nano-particle sol A is 0.5- 3 kg/ton.
• the retention of SiO 2 in the handsheets is about 70%-85%. The paper properties are not obviously changed.

Landscapes

• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Organic Chemistry (AREA)
• Dispersion Chemistry (AREA)
• Paper (AREA)
• Silicon Compounds (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=37888557

Family Applications (1)

Country Status (7)

Family Cites Families (5)

• 2005
  • 2005-09-26 CN CNA2005101049980A patent/CN1940178A/zh active Pending
• 2006
  • 2006-09-22 CA CA002623459A patent/CA2623459A1/fr not_active Abandoned
  • 2006-09-22 EP EP06791074A patent/EP1967494A1/fr not_active Withdrawn
  • 2006-09-22 KR KR1020087010232A patent/KR20080083109A/ko not_active Application Discontinuation
  • 2006-09-22 JP JP2008531514A patent/JP2009510271A/ja not_active Withdrawn
  • 2006-09-22 AU AU2006294284A patent/AU2006294284A1/en not_active Abandoned
  • 2006-09-22 WO PCT/CN2006/002484 patent/WO2007033601A1/fr active Application Filing

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events